The single biggest new feature in Python 3.13 is something Python users have anticipated for ages: a version of Python that allows full concurrency between Python threads by removing the Global Interpreter Lock.
When Python's free-threaded version was first announced, the plan wasn't to immediately replace the GIL-equipped version of Python. Instead, Python users would have the option to install Python's free-threaded build side-by-side with the regular version and select between them as needed.
Binary releases of Python 3.13 for Microsoft Windows and macOS come with an option in the installer to set up the free-threaded build. If you select this option, two Python executables are installed: python and python3.13t.
On Microsoft Windows, the py tool gives you the option to choose between builds, just as you'd use it to choose an overall version of Python.
Collection
[
|
...
]